1. Field of Invention
This invention relates to wireless network communicating link, specifically to redundant wireless network link formed by redundant wireless network devices.
2. Description of Prior Art
Wireless communication system utilizes electro-magnetic wave as media to carry messages in between transmitting and receiving devices. In the art of fixed wireless networking, two wireless network equipments communicating to each other form a wireless network link. The wireless network link links the two networks that behind the wireless network equipments. Electro-magnetic wave propagating in the free space may be affected by many factors. Thus causes the quality of the wireless network link unstable. Further more, wireless networking radio hardware malfunction often causes wireless network communication link to be at poor quality, or even broken.
Fixed wireless networking is a duplex digital data networking system. Normally people deploy point to point and/or point to multi-point network with one Access Point (AP) communicating to the far end Subscribe Unit (SU) devices. To build an outdoor wireless network, people need to build a POP site on top of a high building or a tower, of which, a POP may comprise one or more APs and other network devices, such as router and/or ATM switch. The APs communicate to one or more far end SUs form point to point and/or point to multi-point wireless network links.
AP, SU type of wireless network has no redundancy feature. Partially link optimization can be achieved by turn on the choosing preferred AP function of the SU.
In the prior art of fixed outdoor wireless networking, the network device AP and SU are single channel devices. Network redundancy cannot be achieved. Turning on the SU feature of choosing preferred AP, increases the complexity of the network and causes the network unstable or fail.
Hardware failure will cause the communication between AP and SU cease; an unexpected interference at current wireless channel will also cause the communication between AP and SU to be unstable or cease. When link failure happens, it is impossible to keep the current communication between AP and SU until manual maintenance and hardware replacement. Obviously, this type of wireless network system cannot be used in mission critical applications.